The present invention relates to a video tape recorder (hereinafter, referred to as VTR) having an index scan function for searching at a high speed a starting position of each program on a magnetic tape in response to an index signal for indicating a starting position of a program and a picture-in-picture (hereinafter, referred to as PIP) function for forming and outputting a video signal for PIP display, and more particularly to an apparatus and the method thereof for outputting video signals for one screen at the starting position of the program corresponding to each index signal and automatically searching the starting position of the program required by the user.
The conventional VTR includes a VTR comprising a so-called index scan function performing pulse-width modulation of a control signal in response to an index signal indicating the starting position of each program recorded on a magnetic tape and recording the modulated control signal, to search for the recorded program utilizing such an index signal as an index scan function. A VISS (Video Index Search System) utilizing only an index signal or a VASS (Video Address Search System) utilizing an address signal indicating an absolute address of a tape in addition to the above described index signal are generally used. The VTR with such an index scan function is described in for example, Japanese Laid-open Patent No. 201249/1984 and "Electronics Life", Journal issued by NHK, March, 1987 (pp. 123-126).
More specifically, in a VTR with the above described index scan function, a control track having a control signal recorded thereon is formed on a magnetic tape to control tape travel. Actually, the duty ratio of the control signal (pulse) is changed depending on the data content of an index signal indicating the starting position of each recorded program. More specifically, in such a VTR even in a fast forward mode (FF mode) or a rewind mode (REW mode) in which a tape is traveled at high speed by half-loading control, the tape is traveled with a control head that records and reproduces a control track in contact with a control track of the tape. In particular, when an index scan mode is set, the change of the duty ratio of the control signal, i.e., the index signal is detected by the control head during high-speed traveling of the tape, so travel control comes about through only short intervals in the normal reproducing mode by a reversing or not reversing of the tape travel a constant amount each time the index signal is detected, thus reproducing, in order, the start position of a recorded program.
On the other hand, the conventional VTR includes a VTR comprising a PIP function utilizing a time-base compression of either one of a video signal reproduced from a recorded medium or a video signal received by a tuner contained in the VTR and a video signal externally inputted and by combining the aforementioned compressed signal another video signal, a video signal for picture-in-picture display in which a subscreen is inserted into a part of a main screen is formed and outputted the same. The VTR with such a PIP function is actually described in "Sanyo Technical Review" published in 1987, Vol. 19, No. 1, pp. 76-84.
The conventional VTR with the above described index scan function is adapted so that the output of the received video signal is interrupted to output the reproduced video signal every time the index signal is detected during the index scan mode.
Additionally, a VTR has been put into application in which reproduced pictures are sequentially reduced and displayed every time the index signal is detected, to form a plurality of subscreens without forming the above described main screen in the VTR with the above described index scan function. Such a VTR is disclosed in Japanese Laid-open Patent No. 141873/1987.
As described above, the conventional VTRs are very inconvenient since the reproduced video signal is displayed with the received video signal or the externally inputted video signal, every time the index signal is detected during the index scan mode.